The brain area that stores musical memories appears to be less affected by the disease

Without fully understanding why, music is one of the few tools therapists have to combat the progression of Alzheimer’s. Despite the devastation this disease causes in the brain—and particularly in memory—a large number of patients retain their musical memories even in the later stages. Now, a study points to the possible reasons behind this phenomenon: music is stored in different areas of the brain than other types of memories.

The temporal lobe, the part of the brain that extends from the temple to the area behind the ear, is, among other things, the human jukebox. It is where our auditory memory is managed, including songs. Studies on individuals with brain injuries support the idea that we store music in a network centered in that area. However, the temporal lobe is also one of the first regions to be affected by Alzheimer’s disease. So how is it that many patients no longer know their own name or how to get home, yet still recognize a song that moved them decades ago? How is it that some patients are unable to utter a single word, and yet manage to hum tunes that were popular back when they could still remember?

To try to answer these questions, researchers from several European countries, led by neuroscientists from the Max Planck Institute for Human Cognitive and Brain Sciences in Leipzig (Germany), conducted a two-part experiment. On one hand, they examined which areas of the brain are activated when we hear songs. On the other, once those areas were identified, they analyzed whether these brain regions in Alzheimer’s patients show signs of atrophy or, on the contrary, are more resistant to the disease.

To pinpoint where the brain stores music, the researchers had around thirty healthy individuals listen to 40 sets of three songs. Each trio included one very well-known song taken from the charts since 1977, along with a lullaby and traditional German music. The other two songs in each set were similar in style, tone, rhythm, or mood to the first, but were selected from musical flops—songs that were not well known.

As explained in the journal Brain, the design of the experiment was based on the hypothesis that the experience of hearing music is, for the brain, different from that of remembering it, and that both processes involve different brain networks. During the sessions, the brain activity of the volunteers was recorded using functional magnetic resonance imaging (fMRI). The researchers found that music is stored in areas of the brain that are different from those where other memories are kept.

“At least the crucial aspects of musical memory are processed in brain areas that are not typically associated with episodic, semantic, or autobiographical memory,” says Max Planck neuroscientist and co-author of the study, Jörn-Henrik Jacobsen. “But we must be very cautious when making such absolute statements,” he adds cautiously.